src/svgtiny_css.c

   1 #include <libcss/libcss.h>
   2
   3 #include "svgtiny.h"
   4 #include "svgtiny_internal.h"
   5
   6 static css_error node_name(void *pw, void *node, css_qname *qname);
   7 static css_error node_classes(void *pw, void *node,
   8                 lwc_string ***classes, uint32_t *n_classes);
   9
  10
  11 /**
  12  * Resolve a relative URL to an absolute one by doing nothing. This is
  13  * the simplest possible implementation of a URL resolver, needed for
  14  * parsing CSS.
  15  */
  16 css_error svgtiny_resolve_url(void *pw,
  17                 const char *base, lwc_string *rel, lwc_string **abs)
  18 {
  19         UNUSED(pw);
  20         UNUSED(base);
  21
  22         /* Copy the relative URL to the absolute one (the return
  23            value) */
  24         *abs = lwc_string_ref(rel);
  25         return CSS_OK;
  26 }
  27
  28 /**
  29  * Create a stylesheet with the default set of params.
  30  *
  31  * \param sheet A stylesheet pointer, passed in by reference, that
  32  * we use to store the newly-created stylesheet.
  33  * \param inline_style True if this stylesheet represents an inline
  34  * style, and false otherwise.
  35  *
  36  * \return The return value from css_stylesheet_create() is returned.
  37  */
  38 css_error svgtiny_create_stylesheet(css_stylesheet **sheet,
  39                 bool inline_style)
  40 {
  41         css_stylesheet_params params;
  42
  43         params.params_version = CSS_STYLESHEET_PARAMS_VERSION_1;
  44         params.level = CSS_LEVEL_DEFAULT;
  45         params.charset = NULL;
  46         params.url = "";
  47         params.title = NULL;
  48         params.allow_quirks = false;
  49         params.inline_style = inline_style;
  50         params.resolve = svgtiny_resolve_url;
  51         params.resolve_pw = NULL;
  52         params.import = NULL;
  53         params.import_pw = NULL;
  54         params.color = NULL;
  55         params.color_pw = NULL;
  56         params.font = NULL;
  57         params.font_pw = NULL;
  58
  59         return css_stylesheet_create(&params, sheet);
  60 }
  61
  62
  63 /**************************/
  64 /* libcss select handlers */
  65 /**************************/
  66 /*
  67  * From here on we implement the "select handler "API defined in
  68  * libcss's include/libcss/select.h and discussed briefly in its
  69  * docs/API document.
  70  */
  71
  72
  73 /**
  74  * Retrieve the given node's name
  75  *
  76  * \param pw     Pointer to the current SVG parser state
  77  * \param node   Libdom SVG node
  78  * \param qname  Address at which to store the node name
  79  *
  80  * \return CSS_OK on success, or CSS_NOMEM if anything goes wrong
  81  */
  82 css_error node_name(void *pw, void *node, css_qname *qname)
  83 {
  84         dom_string *name;
  85         dom_exception err;
  86         struct svgtiny_parse_state *state;
  87
  88         err = dom_node_get_node_name((dom_node *)node, &name);
  89         if (err != DOM_NO_ERR) {
  90                 return CSS_NOMEM;
  91         }
  92
  93         state = (struct svgtiny_parse_state *)pw;
  94         qname->ns = lwc_string_ref(state->interned_svg_xmlns);
  95
  96         err = dom_string_intern(name, &qname->name);
  97         if (err != DOM_NO_ERR) {
  98                 dom_string_unref(name);
  99                 return CSS_NOMEM;
 100         }
 101
 102         dom_string_unref(name);
 103
 104         return CSS_OK;
 105 }
 106
 107
 108 /**
 109  * Retrieve the given node's classes
 110  *
 111  * \param pw         Pointer to the current SVG parser state
 112  * \param node       Libdom SVG node
 113  * \param classes    Address at which to store the class name array
 114  * \param n_classes  Address at which to store the length of the class
 115  *                   name array
 116  *
 117  * \return CSS_OK on success, or CSS_NOMEM if anything goes wrong
 118  *
 119  * \note CSS_NOMEM is not possible in practice as of libdom-0.4.1,
 120  *       because the underlying libdom function never fails
 121  */
 122 css_error node_classes(void *pw, void *node,
 123                 lwc_string ***classes, uint32_t *n_classes)
 124 {
 125         UNUSED(pw);
 126         dom_exception err;
 127
 128         err = dom_element_get_classes((dom_node *)node, classes, n_classes);
 129
 130         /* The implementation does not do it, but the documentation
 131            for dom_element_get_classes() says that a DOM_NO_MEM_ERR is
 132            possible here, so we handle it to be on the safe side. */
 133         if (err != DOM_NO_ERR) {
 134                 return CSS_NOMEM;
 135         }
 136
 137         return CSS_OK;
 138 }